Overview
The Thousand Lakes Wilderness Loop is the most demanding day hike in Lassen National Forest, covering 12.4 miles with over 2,200 feet of elevation gain through the Thousand Lakes Wilderness, a 16,000-acre roadless area north of Lassen Volcanic National Park. The route visits multiple alpine lakes, climbs to volcanic ridge viewpoints, and passes through old-growth red fir stands that rival anything in the region.
Despite the dramatic terrain, the Thousand Lakes Wilderness receives very few visitors. The access roads are rough, the trailhead is unmarked on most GPS apps, and the loop requires navigation skills beyond what most casual hikers bring. Those who arrive find a genuinely wild experience within a few hours of Redding and the Sacramento Valley.
The Route
Trailhead to Barrett Lake (Mile 0 to 3.0)
From Tamarack Trailhead, the trail climbs immediately through red fir and lodgepole into the wilderness boundary. The first 3 miles gain most of the elevation on the northern half of the loop, reaching Barrett Lake (7,100 ft) in a classic basalt bowl setting. The lake is small but clear, with a flat camping area on the eastern shore.
Barrett Lake to Eiler Lake via Crater Peak (Mile 3.0 to 6.5)
The trail continues south from Barrett Lake and climbs steeply to the ridge below Crater Peak (8,677 ft). A short spur trail gains the actual summit; the main loop skirts the western shoulder. Views from the ridge include Lassen Peak to the south, Mount Shasta to the north, and the Sacramento Valley on clear days. The trail descends steeply from the ridge to Eiler Lake, the largest lake on the route, at about 6,800 feet.
Eiler Lake to Magee Lake (Mile 6.5 to 8.5)
The trail winds through open basalt plateau country from Eiler Lake to Magee Lake, losing and regaining modest elevation. This section has the most wildflowers in July and passes several smaller unnamed ponds. Magee Lake sits in a shallow bowl with good camping.
Return to Trailhead (Mile 8.5 to 12.4)
The loop's return leg descends through old-growth red fir forest along a stream drainage before climbing back to the trailhead. This is the most forested section, providing welcome shade on warm afternoons.
When to Hike
July through August is the primary window. Snow often lingers on the Crater Peak ridge through late June, and the trail can be difficult to follow across snow-covered plateau sections. Wildflowers peak in mid-July.
September offers the best combination of clear skies, manageable temperatures, and minimal crowds. The mosquito season typically ends after mid-August in this area.
Before attempting this as a day hike, honestly assess fitness. The 12.4 miles with 2,200 feet of gain is appropriate for experienced hikers; consider an overnight trip to fully appreciate the wilderness.
What to Bring
Many hikers carry 3 liters of water for this full-day route. Water is available at all three lakes and from several streams, but treat or filter everything. Individual hydration needs vary with pace, temperature, and fitness.
Navigation tools beyond a smartphone GPS are strongly recommended. The Thousand Lakes Wilderness is not heavily signed, and the volcanic plateau sections can be disorienting. Download offline maps and bring a paper backup.
Emergency gear (rain layer, emergency bivy, headlamp) is worth carrying given the remote nature of this wilderness. Afternoon thunderstorms are common in July; be off exposed ridges by early afternoon.
Trailhead Access
The Tamarack Trailhead is reached via Forest Road 16 off Highway 89 north of Hat Creek. The last several miles are unpaved and rough; high-clearance vehicles are strongly recommended. The trailhead is small and may not appear on consumer GPS devices; download the USFS motor vehicle use map before departure.
No permit is required for day hiking or camping in the Thousand Lakes Wilderness (as of 2026). No restrooms at the trailhead. Dogs are allowed on leash.
Nearby
For those building a multi-day trip around the northern Lassen National Forest, the Magee Peak Trail covers some of the same high terrain from a different trailhead and is worth comparing. The Twin Lakes Trail and Caribou Lake Trail in the Caribou Wilderness provide lower-commitment alternatives for earlier in the season.
Check current fire restrictions and road closures at Checking Conditions Before You Go before this trip. Practice Leave No Trace 7 Principles, particularly around lake margins and on the fragile volcanic soils of the plateau.